Related Clues:

• Either "T" in "AT&T," when abbreviated
• Business card info: Abbr
• Two-dash ID
• 987-65-4321, for one
• Util
• Office no
• Invoice heading no
• "Aviv" header
• Taxation ID
• Application datum: Abbr
• Personal identifier, for short
• Many an ID thief's target
• Form W-9 info
• Smartphone no
• Filing ID